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951.
Presence of the red leg syndrome (RLS) was documented through bacterial and histological examinations in the endangered Kaiser's mountain newt Neurergus kaiseri obtained from a pet shop. The individuals which were severely infected showed lethargy, appetite loss, weight loss, abdominal skin redness and skin ulcers on hind legs. This study reveals the presence of two bacteria causing RLS on the skin of captive AT. kaiseri including Proteus vulgaris and Bacillus cereus. Sections of skin in affected areas and internal organs were examined through standard histological procedures. Histologically, epidermal necrosis and ulcers, epidermal gland depletion, myositis and subcutaneous edema, gastric submucosal edema and hepatomegaly were seen. There were also correlations between the microbial infection and structural changes in tissues of Kaiser's mountain newt. The severity of the structural changes are related to the level of microbial infection in the target organs and could be sustained by the isolation of P. vulgaris and other pathogens. The presence of the infective bacterial population and their interaction on the skin of the newt may have changed the normal skin flora and facilitate the prevalence of other disease. 相似文献
952.
953.
Hamidreza Ghasemi Bahraseman Kamran Hassani Mahdi Navidbakhsh Daniel M. Espino Zahra Alizadeh Sani Nasser Fatouraee 《Computer methods in biomechanics and biomedical engineering》2014,17(16):1821-1834
The aim of this study was to measure the cardiac output and stroke volume for a healthy subject by coupling an echocardiogram Doppler (echo-Doppler) method with a fluid–structure interaction (FSI) simulation at rest and during exercise. Blood flow through aortic valve was measured by Doppler flow echocardiography. Aortic valve geometry was calculated by echocardiographic imaging. An FSI simulation was performed, using an arbitrary Lagrangian–Eulerian mesh. Boundary conditions were defined by pressure loads on ventricular and aortic sides. Pressure loads applied brachial pressures with (stage 1) and without (stage 2) differences between brachial, central and left ventricular pressures. FSI results for cardiac output were 15.4% lower than Doppler results for stage 1 (r = 0.999). This difference increased to 22.3% for stage 2. FSI results for stroke volume were undervalued by 15.3% when compared to Doppler results at stage 1 and 26.2% at stage 2 (r = 0.94). The predicted mean backflow of blood was 4.6%. Our results show that numerical methods can be combined with clinical measurements to provide good estimates of patient-specific cardiac output and stroke volume at different heart rates. 相似文献
954.
Masoud Sheidai Somayeh Ziaee Fatemeh Farahani Seyed-Mehdi Talebi Zahra Noormohammadi Yeganeh Hasheminejad-Ahangarani Farahani 《Biologia》2014,69(1):32-39
The genus Linum L. (Lineacea) has over 15 species, subspecies or ecotypes in Iran. These species show extensive geographical distribution and form many local populations throughout the country. Linum album is herbaceous medicinal plant containing important lignans such as podophyllotoxin (PTOX) and 6-methoxy podophyllotoxin (MPTOX), which have antiviral and anticancer properties. Studying the genetic and morphological diversity of different geographical populations produces detailed knowledge about population divergence and identification of the infra-species taxa if at all they are present. Moreover, the populations that differ in their genetic content and structure may also differ in their chemical and medicinal properties. The present study considers morphological and genetic diversity analyses of 20 L. album geographical populations by using nuclear ISSR markers, genome size, and cytogenetic characteristics. These populations differed significantly in many of their quantitative morphological characters and in some of their qualitative features. They also differed significantly in their molecular characteristics and genome size. Details of morphological and molecular variations are reported and discussed. 相似文献
955.
Salah A. Al-Trawneh Jalal A. Zahra Marwan R. Kamal Mustafa M. El-Abadelah Franca Zani Matteo Incerti Andrea Cavazzoni Roberta R. Alfieri Pier G. Petronini Paola Vicini 《Bioorganic & medicinal chemistry》2010,18(16):5873-5884
A simple and efficient synthesis of 6-fluoro-4-oxopyrido[2,3-a]carbazole-3-carboxylic acids (13a–e) and a structurally related 6-fluoro-4-oxothieno[2′,3′:4,5]pyrrolo[3,2-h]quinoline (13f) was achieved via Stille arylation of 7-chloro-6-fluoro-8-nitro-4-oxoquinoline-3-carboxylate and a subsequent microwave-assisted phosphite-mediated Cadogan reaction. The new compounds were tested for their in vitro antimicrobial and antiproliferative activity. The ability of 13a–f to inhibit the activity of DNA gyrase and topoisomerase IV was also investigated. The thieno isostere (13f) emerged as the most active antibacterial, while the 9-fluoro derivative (13e) was the most potent against multidrug-resistant staphylococci. Compounds 13a, 13c–f displayed growth inhibition against MCF-7 breast tumor and A549 non-small cell lung cancer cells coupled with an absence of cytotoxicity toward normal human-derm fibroblasts (HuDe). Compound 13e was the most active anticancer against MCF-7 cells, with greater potency than ellipticine (IC50 0.8 and 1.6 μM, respectively). The most active compounds in this series show promise as dual acting anticancer and antibacterial chemotherapeutics. 相似文献
956.
Mehdi D. Davari Homayoon Bahrami Zahra Zolmajd Haghighi Mansour Zahedi 《Journal of molecular modeling》2010,16(5):841-855
The one step intramolecular thione-thiol tautomerism of 1,2,4-triazole-3-thione and its disubstituted derivatives has been
studied through the use of electronic structure methods. Due to the absence of experimental data for the parent molecule of
1,2,4-triazole-3-thione the structure and energetics of aforementioned tautomers were derived using various basis sets and
levels including HF, B3LYP, and MP2 methods. The gas phase results show that in all different levels of theory the most stable
tautomer is the thione form. It has also been revealed that B3LYP/6-31G(d,p) level is quite well suited and reliable to investigate
these kinds of tautomerism. To account the influence of substituents on the mentioned tautomerization, the tautomerism and
conformational properties as well as vibrational analysis of 20 halophenyl and isopyridyl derivatives were investigated using
B3LYP/6-31G(d,p) calculations. In all cases the calculations indicate that substituents have no considerable effects on relative
stabilities and energy barriers for the thione-thiol proton transfer and the thione forms are the predominant species in the
gas phase. In order to figure out the relative stabilities of the species involved in the tautomerism, geometrical and natural
bond orbital (NBO) analyses have been employed. It has also been shown that the computed vibrational frequencies of tautomers
with different scaling factors could be used to interpret the vibrational frequencies in IR spectrum of similar species. 相似文献
957.
Valiollah Babaeipour Mahdi Pesaran Haji Abbas Zahra Sahebnazar Reza Alizadeh 《Bioprocess and biosystems engineering》2010,33(5):591-598
Development of inexpensive and simple culture media is always favorable for recombinant protein over-expression in E. coli. The effects of medium composition on the production of recombinant human granulocyte-colony stimulating factor (rh-GCSF)
were investigated in batch culture of E. coli BL21 (DE3) [pET23a-hgcsf]. First, the optimum medium for production of rh-GCSF was determined; and, then it was shown that mixture of amino acid addition
at induction time, which was determined on the basis of amino acids frequency in the recombinant protein, increases recombinant
protein expression level significantly. Furthermore, the effect of glucose concentration on productivity of rh-GCSF was investigated;
20 g/l of glucose will result in maximum attainable biomass and rh-GCSF in this process. At optimum conditions, a cell dry
weight of 10.5 g/l, an expression level of about 35% of total cellular protein, rh-GCSF concentration of 1.75 ± 0.1 g/l, and
overall rh-GCSF yield of 165 ± 5 mg/g were obtained. 相似文献
958.
Chronic inflammation associated with tumor necrosis factor (TNF)-alpha and reactive oxygen species (ROS) is the hallmark of tuberculosis. Mycobacterium tuberculosis (MTB) directly stimulates human monocytes to secrete TNF-alpha. We show the augmented expression of TNF-alpha mRNA in MTB-infected monocytes by cellular activation and ROS was suppressed by allicin in a dose-dependent manner. Also, allicin enhanced the glutathione peroxidase activity, which correlated inversely with the downregulation of ROS and TNF-alpha in MTB-infected monocytes. Hence, allicin may prove to be a valuable natural antioxidant in combating tuberculosis. 相似文献
959.
Background
Virulent Mycobacterium leprae interfere with host defense mechanisms such as cytokine activation and apoptosis. The mitochondrial pathway of apoptosis is regulated by the Bcl-2 family of proteins. Expression of Fas ligand and apoptotic proteins is found in leprosy lesions and M. leprae has been shown to activate pro-apoptotic Bcl-2 genes, Bak and Bax. However, the mechanism by which M. leprae modulates apoptosis is as yet unclear. We investigated expression of apoptotic genes in THP-1 monocytes in response to infection by M. leprae and non-pathogenic M. bovis BCG. 相似文献960.
Iraj Nabipour Katayon Vahdat Seyed Mojtaba Jafari Raha Pazoki Zahra Sanjdideh 《Cardiovascular diabetology》2006,5(1):1-6